The occurrence of fruit bodies of mycorrhizal fungi under differently aged plantations of lodgepole pine and Sitka spruce on deep peat was examined. Broadly similar patterns of occurrence in relation to stand development were found in both species, but with some shift in the dominance of Lactarius rufus to older stands in Sitka spruce compared to lodgepole pine. The fruit-body successions indicated were Laccaria/Paxillus -Lactarius-Cortinarius/ Inocybe-Russula for lodgepole pine and Laccaria/Paxillus -Inocybe-Cortinarius-Lactarius for Sitka spruce. Changes in the saprotrophic agaric flora were also noted. Nolanea cetrata, Clitocybe sp. and Collybia spp. were present in greater abundance in the lodgepole pine stands, whereas a restricted flora of Marasmius androsaceus and Mycena spp. occurred under Sitka spruce. The patterns of association with tree species, together with seasonality of occurrence, are discussed in relation to resource quality of the litter and possible climatic and edaphic site characteristics.